1. Field of the Invention
The present invention relates to diuretically active pharmaceutical compositions useful as quick-acting diuretics.
2. Description of the Prior Art
It has been known in medical practice to use furosemide (4-chloro-N-furfuryl-5-sulfamoylanthranilic acid) for the rapid water removal in edemic conditions.
Furosemide is used above all in fluid accumulations resulting from heart insufficiency, liver cirrhosis and nephrotic syndrome. It is also useful via intravenous application in the therapy for lung and brain edemas.
Furosemide is given intravenously when a very rapid dehydration is desired or when oral application is impossible. Potassium excretion increases in furosemide treatment. When using furosemide, it is often necessary to replace potassium losses through increased oral delivery. Under the aspect of potassium loss, it is reasonable to use, in combination with furosemide, potassium retaining aldosterone antagonists or triamterenes, (2,4,7-triamino-6-phenylpteridines) (O. Schuck and J. Stribrna, Handbook of Diuretic-Therapy, pp. 87-92, Urban and Schwarzenberg, Munich, Berlin, Vienna, 1971).
Researches relating to the combinations of furosemide with mercuric thiazide, hydrothiazide, and disulfonamide diuretics yielded an additive effect concerning the diuretic and salt uretic effects.
Combinations with etacrynic acid (2,3-dichloro-4-(2-methylene butyryl)-phenoxy)-acetic acid) increase the effect when both diuretics are dispensed in submaximally acting doses.
In the therapeutic practice there is therefore a need for active agents useful in the quick initiation of a forced diuresis.
Until now, furosemide has preponderantly been used for this purpose as a "high ceiling diuretic". Thiazide-diuretics, which belong to the group of the so-called "low ceiling diuretics," are not appropriate as monotherapeutic or also in combinations, for the introduction of a forced diuresis.
The combination of furosemide with triamterenes has the advantage that the potassium loss (resulting as a consequence of the use of furosemide) is inhibited. This combination however is not appropriate for its use in intravenous delivery.